This invention relates to devices for providing information, in the form of electrical signals, about the position of a source or sink of electric current relative to two or more current-carrying electrodes. In particular, it relates to devices for converting selected touch points or positions on a surface (reflecting hand motions) into electric signals to provide an interface between man and machine. It also relates to systems for producing electric fields with predetermined characteristics.
This invention is an improvement on U.S. Pat. No. 4,293,734, titled "TOUCH PANEL SYSTEM AND METHOD", and issued to William Pepper, Jr. on Oct. 6, 1981; U.S. Pat. No. 4,198,593, titled "SYSTEM FOR PRODUCING ELECTRIC FIELD WITH PREDETERMINED CHARACTERISTICS AND EDGE TERMINATIONS FOR RESISTANCE PLANES THEREFOR", and issued to William Pepper, Jr. on Apr. 15, 1980; and U.S. Pat. No. 4,371,746, entitled "EDGE TERMINATIONS FOR IMPEDANCE PLANES", and issued to William Pepper, Jr. on Feb. 1, 1983.
The present invention, in one form, substitutes plain conductive elements for the resistance element or impedance layer described in said U.S. Pat. No. 4,293,734, thus permitting simpler and less expensive touch panels. In another form, it makes said Touch Panel System and Method practical for two-dimensional applications where the size of the touch panel is very small in one dimension relative to the other. It further provides a means for making a touch panel with good linearity in two dimensions using resistive material with good uniformity in only one dimension. The present invention is thus an improvement in the art of human-machine interfacing.
This invention is also an improvement on William Pepper, Jr.'s pending patent application Ser. No. 068,802 titled "HAND-HELD MUSICAL INSTRUMENT AND SYSTEMS INCLUDING A MAN-MACHINE INTERFACE APPARATUS", filed Aug. 22, 1979, now U.S. Pat. No. 4,430,917. It adds a second dimension of control to the pitch-determining elements of that patent application and thus is an improvement in electronic musical instruments.